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Note that this test addresses total species density, not just native species density (but see Alternative <br />• Test C below). Noxious weeds are omitted. The point of addressing total species density, including <br />annual /biennial species and introduced species, is that the total species density is arguably a strong <br />indication of the existence of niche spaces that could eventually be occupied by the native forb and <br />woody plant species typical of the pre - mining plant communities. <br />The final step for this assessment will be comparison of the mean total species density of the BRB to <br />the reference area- derived standard number (above). If the reclaimed area mean exceeds the <br />standard, the Test A is passed. If the BRB mean is less than the standard, a hypothesis test will be <br />undertaken. This would be accomplished using the expression set forth above for a one - sample t- <br />test comparing the reclaimed area species density mean, <br />Deleted: --- ----Page Break __- -- ------- <br />• Alternative Test C): Assessment of the Distribution of Species Density Among Lifeforms Page Break <br />in Comparison to the Reference Areas <br />This test relates to the distribution of the presence of species among the various lifefoxms in <br />comparison to the reference areas. This standard will use the Motyka similarity index to assess the <br />resemblance of the distribution of species density by lifeform of the reclamation vegetation to that of <br />the reference areas. Because the average internal resemblance (i.e. between - sample similarity) of <br />applicable reference areas for species density data is often in the range of 70 %, the proposed <br />standard is 63% (0.9 x 70 %). (For this determination, data from the extended reference areas <br />(Sagebrush, Mountain Brush, and Aspen) from the nearby Seneca II -W Mine were examined. The <br />Seneca II -W extended reference areas extend across sections of landscape more comparable in <br />dimension to the BRB areas than are the comparatively small Seneca II reference areas. Thus, they <br />are thought to be more indicative of pre - mining inter -stand community diversity). <br />The Motyka similarity index will be used as follows: <br />IS_ = 2c / (a + b) <br />• Where <br />a =total of species density values for lifefoxms of the reclaimed areas <br />b = total of species density values for the lifefoxms of the reference area* <br />c = the sum of the smaller of the species density values for lifeforms of the reclaimed and <br />reference areas* <br />* 'Weighted average Izfeforrrr species density wring the Seneca H Reference Areas (weighted hared on 83% original <br />extent of Mountain Brush / Aspen and 17% original extent of Sagebrush). <br />Only cover by vascular plants will be included. Lifeforms to be used will include: <br />Annual /biennial forbs <br />Annual grasses <br />Perennial forbs /Subshrubs <br />Perennial cool season grasses <br />• Alternative Test D): Assessment of the Presence of Native Species <br />The third alternative assessment of the species diversity of reclaimed lands makes direct reference to <br />the presence of native western North American plant species in reclaimed areas. <br />ESCO Associates 13 -13 -9 TR40 *03/06 <br />